Non-invasive measurement of renal perfusion and oxygen metabolism to predict postoperative acute kidney injury in neonates and infants after cardiopulmonary bypass surgery.

BACKGROUND: The pathophysiology of acute kidney injury (AKI) after cardiopulmonary bypass surgery for congenital heart disease is not completely understood. The aim of this study was to carry out a prospective analysis of the diagnostic value of non-invasive monitoring of renal oxygenation and microcirculation by combining laser Doppler flowmetry and tissue spectrometry. METHODS: In 50 neonates and infants who underwent repair (n = 31) or neonatal palliation (n = 19) of congenital heart disease with cardiopulmonary bypass, renal oxygenation, and microcirculatory flow, the approximate renal metabolic rate of oxygen and Doppler-based renal resistive index were determined after surgery. Correlations between these parameters and the occurrence of AKI according to the Pediatric Risk, Injury, Failure, Loss, End Stage Renal Disease criteria were investigated. RESULTS: Acute kidney injury occurred in 45% of patients after repair and in 32% after palliation. Renal oxygenation was significantly lower and the approximate renal metabolic rate of oxygen significantly higher in patients with AKI (P < 0.05). The microcirculatory flow was significantly higher in patients with AKI after neonatal palliation (P < 0.05), whereas renal resistive index was significantly higher in patients with AKI after repair (P < 0.05). The sensitivity of renal oxygenation, metabolic rate of oxygen, microcirculation, and resistive index in predicting AKI was 78-80, 73-78, 64-83, and 71-74%, respectively, with a specificity of 63-65, 54-75, 64-78, and 46-74% (area under the curve: 0.73-0.75, 0.68-0.83, 0.52-0.68, and 0.60-0.75), respectively. CONCLUSIONS: Monitoring of renal oxygen metabolism allows early prediction of AKI in infants after cardiac surgery. In contrast, renal resistive index does not allow prediction of AKI after neonatal palliation with aortopulmonary shunt establishment.

A new method for determining the insertion depth of tracheal tubes in children: a pilot study.

BACKGROUND: Choosing the correct insertion depth of tracheal tubes is crucial for successful airway management in paediatrics. Currently used formulas are based on patient characteristics such as age, body weight and height. The aim of the study is to devise and evaluate more suitable body surface area based diagrams for predicting the correct tracheal insertion depth. METHODS: Calculated insertion depth according to currently used formulas, primary insertion depth and insertion depth corrected by chest radiography ('gold standard') were collected from 237 children. Age, body weight, height and body surface area were noted. Body surface area based diagrams were devised and prospectively evaluated in another set of 123 paediatric patients. RESULTS: Tracheal tube position according to currently used formulas had to be corrected in 37% of all intubations. New body surface area based diagrams were created. In 20.3%, depth of the tracheal tube had to be corrected according to the new body surface area based diagrams. CONCLUSIONS: The body surface area based diagrams may be a reliable tool for predicting the correct tracheal insertion depth in children.

[Combination of Excessive Weight Gain and Interleukin-8: A Possible Predictor of Necrotising Enterocolitis in Neonates?]. / Kann ein Gewichtssprung in Kombination mit einem Anstieg des Interleukin-8 eine nekrotisierende Enterokolitis bei Neonaten vorhersagen?

BACKGROUND: Weight gain before the clinical diagnosis of necrotising enterocolitis (NEC) is described as a predictive factor. HYPOTHESIS: Weight gain of more than 5% one day prior to clinical suspicion plus increase of plasma Iinterleukin-8 (IL-8) are predictive for NEC. METHODS: 48 infants with diagnosis of NEC stage II and III were enrolled in a case-control study. Oral and parenteral nutrition, diuresis and kinetics of weight and of IL-8 were documented. RESULTS: 31 infants with NEC-II and 17 infants with NEC-III were enrolled. Weight gain>5% occurred in 35.3% of NEC-III, in 0% of NEC-II and in 4.2% of the control group. IL-8 increased significantly [NEC-III (6 561.4 pg/mL) vs. NEC-II: (326.7 pg/mL) vs. control group (38.9 pg/mL); p<0.05]. Sensitivity of IL-8 in NEC-II was 87.10% (70.15-96.25) and in NEC-III 100.00% (80.33-100.00). Sensitivity of weight gain was 0.00% (0.00-11.32) in NEC-II and 35.29% (14.30-61.65) in NEC-III. CONCLUSION: Weight gain>5% was found in only 35.3% of the cases with NEC-III. Combination of weight gain and IL-8 did not improve the diagnosis of NEC.

Diagnostic value of immature myeloid information in early-onset bacterial infection in term and preterm neonates.

BACKGROUND: For quick detection of neonatal early-onset bacterial infection (EOBI) pro-inflammatory cytokines like Interleukin-6 (IL-6) and Interleukin-8 (IL-8) in combiantion with C-reactive Protein (CRP) have been used. Automated determination of immature myeloid information (IMI) seems to be an additional useful tool in the diagnosis of NBI. OBJECTIVE: To compare the diagnostic value of IMI, I/T-Ratio, plasma IL-6 and IL-8 levels and CRP in term and preterm neonates at time of clinical suspicion of EOBI. PATIENTS AND METHODS: 31 preterm and 123 term neonates with clinical and serological signs of EOBI were analysed. 91 preterm and 159 term neonates with risk factors but without proven EOBI served as non-infected controls. RESULTS: Neonates with EOBI showed significantly elevated IMI levels at time of first clinical suspicion of EOBI (Preterm: 1 028/µL (38-8 759) vs. 289/µL (6-3 126); Term: 1 268/µL (48-14 035) vs. 856/µL (19-5 735); p<0.05 respectively). I/T-Ratio, IL-6, IL-8 and CRP values were significantly higher in preterm and term neonates with EOBI (p<0.05). Sensitivity of IMI at a cut-off level of 650/µL was 84.2% [95%-CI: 74.0-91.6%] in preterm and 65.4% [95%-CI: 56.8-73.3%] in term infants. Specificity was 66.7% [95%-CI: 47.1-82.7%] and 53.9% [95%-CI: 43.8-63.7%], respectively. Combination of different infection parameters improved sensitivity up to 93.5% and specificity up to 98.9%. CONCLUSION: The diagnostic value of IMI in diagnosing EOBI in preterm and term neonates is not comparable to IL-6, IL-8 and CRP. Combination of IMI-Channel with IL-6, IL-8 or CRP improves their sensitivity, specificity and predictive value.

Safety, efficacy and response to a hydrocortisone rescue therapy protocol in children with refractory hypotension after cardiopulmonal bypass.

Little is known about which paediatric patients respond to hydrocortisone rescue therapy (HRT) with improvement of haemodynamic stability in refractory hypotension after cardiopulmonal bypass. Data were gathered retrospectively from children who received HRT in refractory hypotension after cardiopulmonary bypass in the period from 2000 to 2010. One hundred and sixty-six out of 1,273 children, 150 <1 year and 16 >1 year were enrolled. HRT improved haemodynamics significantly, increased blood pressure, decreased the vasoactive-inotropic score and plasma lactate concentrations in all children >1 year and in 82 % (123 out of 150) of the infants <1 year. Non-responders <1 year were significantly younger, lighter, mostly male infants and had longer cardiopulmonary bypass support time. Serum lactate and paediatric risk of mortality score were significantly higher in non-responders at time of initiation of HRT. Mortality was significantly higher in non-responders versus responders (2.44 vs. 13.5 %; p = 0.0008). HRT caused no adverse effects like electrolyte disturbances or hyperglycaemia. HRT in refractory hypotension after paediatric cardiac surgery is safe but not all infants <1 year show haemodynamic response to HRT. Non-response to HRT is associated with significantly higher mortality.